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Brain Death
&
Organ Donor Management
William Snyder, RN, BSN, CPTC
Organ Procurement Coordinator
University of Wisconsin
Organ Procurement Organization
1-866-UWHC OPO
(1-866-894-2676)
Effective Donor Management
• Stabilize the donor – Facilitate brain death
exam or DCD Tool.
• Manage the donor – To optimize the
function and viability of all transplantable
organs.
“
Effective Donor Management
• Requires clinical expertise, vigilance,
flexibility, and the ability to address
multiple complex clinical issues
simultaneously and effectively.
• Requires collaboration among the OPO,
donor hospital critical care staff and
consultants, and transplant program staff.
Effective Donor Management
• Donor care is not usually assumed until
after consent for donation has been
obtained.
• It is appropriate to collaborate prior to
brain death, consent, etc, to prevent
death and keep the option of organ
donation open.
Effective Donor Management
• Revision of existing orders or placement of new
•
•
•
medical orders is intended to:
D/C medications no longer needed or
appropriate (e.g., anticonvulsants, mannitol,
sedatives, antipyretics)
Continue needed medications, or therapy (e.g.,
vasoactive drug infusions, IV fluids and vent
settings)
Create “call orders” that inform bedside
personnel of the goals for physiologic
parameters and alert OPC of changes in donor
status.
Diagnosing
and
Declaring
Brain Death
Uniform Determination of Death Act
An individual who has sustained either:
(1) irreversible cessation of circulatory and
respiratory function
or
(2) irreversible cessation of all functions of the
entire brain, including the brain stem, is
dead. A determination of death must be made
in accordance with accepted medical
standards.
JAMA Nov 13, 1981 – Vol 246, No. 19
Diagnosis of Brain Death
• Brain death is a clinical diagnosis. It can
be made without confirmatory testing if
you are able to establish the etiology,
eliminate reversible causes of coma,
complete fully the neurologic examination
and apnea testing.
• The diagnosis requires demonstration of
the absence of both cortical and brain
stem activity, and demonstration of the
irreversibility of this state.
R. Erff, D.O., Walter Reed Army Medical Center
Etiology of Brain Death
• Severe head trauma
• Aneurismal subarachnoid hemorrhage
• Cerebrovascular injury
• Hypoxic-ischemic encephalopathy
• Fulminant hepatic necrosis
• Prolonged cardiac resuscitation or
asphyxia
• Tumors
R. Erff, D.O., Walter Reed Army Medical Center
Prerequisites to the Diagnosis
Evidence of acute CNS catastrophe
compatible with brain death:
- Clinical or Neuroimaging
Exclusion of reversible medical conditions
that can confuse the clinical assessment:
-
Severe electrolyte, acid base and endocrine disturbance
Absence of drug intoxication and poisoning
Absence of sedation and neuromuscular blockade
Hypotension (suppresses EEG activity and CBF)
Absence of severe hypothermia (core temp < 35 C)
Brain Stem Reflexes
• Cranial nerve examination:
- No pupillary response to light. Pupils midline
-
-
and dilated 4-6mm.
No oculocephalic reflex (Doll’s eyes) –
contraindicated in C- spine injury.
No oculovestibular reflex (tonic deviation of eyes
toward cold stimulus) – contraindicated in ear
trauma.
Absence of corneal reflexes
Absence of gag reflex and cough to tracheal
suction.
Apnea Testing
• Once coma and absence of brain stem reflexes
•
•
•
•
•
have been confirmed  Apnea testing.
Verifies loss of most rostral brain stem function
Confirmed by PaCO2 > 60mmHg or PaCO2 >
20mmHg over baseline value.
Testing can cause hypotension, severe cardiac
arrhythmias and elevated ICP.
Therefore, apnea testing is performed last in the
clinical assessment of brain death.
Consider confirmatory tests if apnea test
inconclusive.
Apnea Testing
• Following conditions must be met before apnea
-
test can be performed:
Core temp > 35.0 C
Systolic blood pressure > 90mmHg.
Euvolemia
Corrected diabetes insipitus
Normal PaCO2 ( PaCO2 35 - 45 mmHg).
Preoxygenation (PaO2 > 200mmHg).
Brain Death in Children
• Clinical exam is same as in adults.
• Testing criteria depends on age of child.
- Neonate < 7 days  Brain death testing is not
valid.
- 7 days – 2 months
- Two clinical exams and two EEG 48 hrs apart.
- 2 months – 1 year
- Two clinical exams and two EEG 24 hrs apart.
- or two clinical exams, EEG and blood flow study.
- Age > 1 year to 18 years
- Two clinical exams 12 hrs apart, confirmatory
study - Optional
Confirmatory Testing
• Purely optional when the clinical criteria are met
unambiguously.
• A confirmatory test is needed for patients in whom
specific components of clinical testing cannot be reliably
evaluated
-
Incomplete brain stem reflex testing
Incomplete apnea testing
Toxic drug levels
Children younger than 1 year old.
Required by institutional policy
R. Erff, D.O., Walter Reed Army Medical Center
Confirmatory Tests for
Brain Death
• Cerebral Blood Flow (CBF) Studies
– Cerebral Angiography
– Nuclear Flow Study
• EEG (when brain scan is not utilized)
Cerebral Angiography
Normal Blood Flow
No Blood Flow
Nuclear Flow Study
Elements of brain
death declaration
• Date
• Time
• Detailed
documentation of
Clinical Exam
including specifics
of Apnea Testing
• Physician signature
What to expect after
brain death
Pathophysiology
• Loss of brain stem function results in systemic
-
-
physiologic instability:
Loss of vasomotor control leads to a
hyperdynamic state.
Cardiac arrhythmias
Loss of respiratory function
Loss of temperature regulation  Hypothermia
Hormonal imbalance  DI, hypothyroidism
Perioperative Management
• Following the diagnosis of Brain Death
 Therapy shifts in emphasis from cerebral resuscitation to
optimizing organ fxn for subsequent transplantation.
 The normal sequelae of brain death results in
cardiovascular instability & poor organ perfusion.
 Medical staff must focus on:
Providing hemodynamic stabilization.
Support of body homeostasis.
Maintenance of adequate cellular oxygenation and
donor organ perfusion.
 Without appropriate intervention brain death is followed
by severe injury to most other organ systems.
Circulatory collapse will usually occur within 48hrs.
Autonomic/Sympathetic
Storm
• Release of
catecholamines from
adrenals (Epinephrine
and Norepinephrine)
results in a hyperdynamic state:
–
–
–
–
Tachycardia
Elevated C.O.
Vasoconstriction
Hypertension
Failure of the Hypothalamus
results in:
• Impaired temperature regulation hypothermia or hyperthermia
• Leads to vasodilation without the ability to
vasoconstrict or shiver (loss of vasomotor
tone)
• Leads to problems with the pituitary ...
Normal Pituitary Gland
• Controlled by the
hypothalamus
• Releases ADH to
conserve water
• Stimulates the
release of thyroid
hormone
Pituitary Failure results in:
• ADH ceases to be produced = Diabetes
Insipidus
• Can lead to hypovolemia and electrolyte
imbalances
• Leads to problems with the thyroid gland
Normal Thyroid Gland
• Produces hormones
that increase the
metabolic rate and
sensitivity of the
cardiovascular system
 Levothyroxine (T4)
 Triiodothyronine (T3)
Thyroid Failure
Leads to:
 Cardiac instability
 Labile blood pressure
 Potential coagulation
problems
Cardiovascular System
Intensive care management
• “Rules of 100’s”
-
Maintain SBP > 100mmHG
HR < 100 BPM
UOP > 100ml/hr
PaO2 > 100mmHg
• Aggressive fluid resuscitative therapy directed at
restoring and maintaining intravascular volume.
SBP > 90mmHg (MAP > 60mmHg) or CVP ~ 10
mmHg.
Neurogenic Pulmonary Edema

Brain death is associated with numerous pulmonary
problems

The lungs are highly susceptible to injury resulting from
the rapid changes that occur during the catecholamine
storm

Left-sided heart pressures exceed pulmonary pressure,
temporarily halting pulmonary blood flow

The exposed lung tissue is severely injured, resulting in
interstitial edema and alveolar hemorrhage, a state
commonly referred to as neurogenic pulmonary edema
Release of Plasminogen
Activator  DIC
 Results from the passage of necrotic brain tissue into the circulation
 Leads to coagulopathy and sometimes progresses further to DIC
 DIC may persist despite factor replacement requiring early organ recovery
(Also affected by hypothermia, release of catecholamines & hemodilution as a result
of fluid resuscitation)
Organ Donor Management
(in a nutshell)
• Hypertension  Hypotension
• Excessive Urinary Output
• Impaired Gas Exchange
• Electrolyte Imbalances
• Hypothermia
Hypotension Management
Fluid Bolus – NS or LR
(Followed by MIVF NS or .45 NS)
Consider colloids
Dopamine
Neosynephrine
Vasopressin
Thyroxine (T4 protocol)
(seriously)
T4 Protocol
Background
• Brain death leads to sudden reduction
in circulating pituitary hormones
• May be responsible for impairment in
myocardial cell metabolism and
contractility which leads to myocardial
dysfunction
• Severe dysfunction may lead to
extreme hypotension and loss of
organs for transplant
T4 Protocol
Bolus:

15 mg/kg Methylpred
20 mcg T4 (Levothyroxine)
20 units of Regular Insulin
1 amp D50W



Infusion:



200 mcg T4 in 500 cc NS
Run at 25 cc/hr (10 mcg/hr)
Titrate to keep SBP >100
Monitor Potassium levels closely!
Vasopressin (AVP, Pitressin)
• Low dose shown to reduce inotrope use
• Plays a critical role in restoring vasomotor
tone
Vasopressin Protocol
 4 unit bolus
 1- 4 u/hour – titrate to keep SBP >100 or MAP >60
Diabetes Insipidus
Management
 Treatment is aimed at correcting hypovolemia
 Desmopressin (DDAVP) 1 mcg IV, may repeat x 1 after
1 hour.
 Replace hourly U.O. on a volume per volume basis with
MIVF to avoid volume depletion
 Leads to electrolyte depletion/instability monitor closely
to avoid hypernatremia and hypokalemia
Diabetes Insipidus
• Goal is UOP 1-3
•
•
ml/kg/hr
Rule of thumb – 500
ml UOP per hour x 2
hours is DI
Severe cases – Notify
OPC. Assess clinical
situation.
Impaired Gas Exchange
Management
• Maintain PaO2 of >100 and a
•
•
•
•
•
•
•
saturation >95%
Monitor ABG’s q2h or as
requested by OPO
PEEP 5 cm, HOB up 30o
Increase ET cuff pressure
immediately after BD
declaration
Aggressive pulmonary toilet
(Keep suctioning & turning q2h)
CXR (Radiologist to provide
measurements & interpretation)
OPO may request bronchoscopy
CT of chest requested in some
cases
Correct Impaired Gas Exchange and
Maximize Oxygenation!
Most organ donors are referred with:
 Chest trauma
 Aspiration
 Long Hospitalization with bed rest resulting in atelectasis or
pneumonia
 Impending Neurogenic Pulmonary Edema
Brain Death contributes to and complicates all
of these conditions
Impaired Gas Exchange
Goals…
• Goals are to maintain health of lungs for
transplant while optimizing oxygen delivery to
other transplantable organs
• Avoid over-hydration
• Ventilatory strategies aimed to protect the lung
• Avoid oxygen toxicity by limiting Fi02 to achieve
a Pa02 100mmHg & PIP < 30mmHg.
Electrolyte Imbalance
Management
Hypokalemia
If K+ < 3.4 – Add KCL to MIVF
(anticipate low K+ with DI & T4 administration)
Hypernatremia
If NA+ >155 – Change MIVF to include more free H20, Free H20
boluses down NG tube (this is often the result of dehydration, NA+
administration, and free H20 loss 2o to diuretics or DI)
Calcium, Magnesium, and Phosphorus
Deficiencies here common…often related to polyuria
associated with osmotic diuresis, diuretics & DI.
Hypothermia
Management
• Monitor temperature
continuously
• NO tympanic, axillary or oral
temperatures. Central only.
• Place patient on hypothermia
blanket to maintain normal
body temperature
• In severe cases (<95
degrees F) consider:
– warming lights
– covering patient’s head with
blankets
– hot packs in the axilla
– warmed IV fluids
– warm inspired gas
Anemia
 Hematocrit < 30% must be
treated
 Transfuse 2 units PRBC’s
immediately
 Reassess 1o after completion
of 2nd unit and repeat infusion
of 2 units if HCT remains
below 30%
 Assess for source of blood
loss and treat accordingly
Incidence of pathophysiologic changes
following Brain Death:
-
Hypotension
Diabetes Insipidus
DIC
Cardiac arrhythmias
Pulmonary edema
Metabolic acidosis
81%
65%
28%
25%
18%
11%
Physiologic changes During Brain Stem Death – Lessons for
Management of the Organ Donor.
The Journal of Heart & Lung Transplantation Sept 2004 (suppl)
Organ Donation Process
• Evaluate organ function
• Labs (& UA) within 6
•
•
•
•
•
•
•
hours of surgery
Type and Screen
Consent signed
Serology testing
Medical Social History
Locate potential
recipients
Manage hemodynamics
Arrange operating room
The Teams...
Your Hospital
- Anesthesia
- Primary Care Physician or Intensivist (For DCD)
- Surgical Technician/Scrub Nurse
- Circulating Nurse
Abdominal Transplant Team
- Surgeon
- Physician Assistant
- Surgical Recovery Coordinator
Cardiothoracic Team
- Surgeon
- Surgical Fellow
- Surgical Recovery Coordinator
Organ Preservation Time
•
•
•
•
•
•
Heart: 4-6 hours
Lungs: 4-6 hours
Liver: 12 hours
Pancreas: 12-18
hours
Kidneys: 72 hours
Small Intestines: 4-6
hours